Resistor grid assemblies used for dynamic braking in machines, such as, electric and diesel-electric locomotives, off-highway machines, and other heavy equipment are well known. Typically, the resistor grid assembly includes a plurality of resistor elements to dissipate the electric power generated during braking of the machine as heat. Thus, the resistor grid assembly may supplement the friction-based brakes and minimizes the wear in friction-based braking components of the machine. However, the generated heat may raise the temperature of adjacent components in the resistor grid assembly and may also lead to failure if the temperature exceeds a critical limit.
U.S. Pat. No. 4,651,124 discloses a heat-dissipating resistor unit having a plurality of connected fan-folded electrically conductive resistor elements. The resistor elements are supported within a rigid frame by studs affixed to loops of the resistance elements and corresponding heat-resistant insulating elements. The heat-dissipating resistor unit further includes an insulating panel of organic material affixed to an inside surface of the frame and a metal heat shield surrounding the heat-resistant insulating elements positioned inwardly from the frame. However, the metal heat shield may need to be supported on the heat-dissipating resistor unit by one or more retaining rings.